Continuous laryngoscopy exercise test: a method for visualizing laryngeal dysfunction during exercise

Exercise-Induced Bronchoconstriction in Children: State of the Art from Diagnosis to Treatment

Exercise-induced bronchoconstriction (EIB) is a common clinical entity in people with asthma. EIB is characterized by postexercise airway obstruction that results in symptoms such as coughing, dyspnea, wheezing, chest tightness, and increased fatigue. The underlying mechanism of EIB is not completely understood. "Osmotic theory" and "thermal or vascular theory" have been proposed. Initial assessment must include a specific work-up to exclude alternative diagnoses like exercise-induced laryngeal obstruction (EILO), cardiac disease, or physical deconditioning. Detailed medical history and clinical examination must be followed by basal spirometry and exercise challenge test. The standardized treadmill running (TR) test, a controlled and standardized method to assess bronchial response to exercise, is the most adopted exercise challenge test for children aged at least 8 years. In the TR test, the goal is to reach the target heart rate in a short period and maintain it for at least 6 min. The test is then followed by spirometry at specific time points (5, 10, 15, and 30 min after exercise). In addition, bronchoprovocation tests like dry air hyperpnea (exercise and eucapnic voluntary hyperpnea) or osmotic aerosols (inhaled mannitol) can be considered when the diagnosis is uncertain. Treatment options include both pharmacological and behavioral approaches. Considering medications, the use of short-acting beta-agonists (SABA) just before exercise is the commonest option strategy, but daily inhaled corticosteroids (ICS) can also be considered, especially when EIB is not controlled with SABA only or when the patients practice physical activity very often. Among the behavioral approaches, warm-up before exercise, breathing through the nose or face mask, and avoiding polluted environments are all recommended strategies to reduce EIB risk. This review summarizes the latest evidence published over the last 10 years on the pathogenesis, diagnosis using spirometry and indirect bronchoprovocation tests, and treatment strategies, including SABA and ICS, of EIB. A specific focus has been placed on EIB management in young athletes, since this condition can not only prevent them from practicing regular physical activity but also competitive sports.

Diagnostic utility of spirometry for children with induced laryngeal obstruction or chronic non-specific cough

PURPOSE

To determine the diagnostic utility of spirometry in distinguishing children with Induced Laryngeal Obstruction (ILO) or chronic non-specific cough (a.k.a. tic cough) from those with mild or moderate to severe asthma.

METHODS

Retrospective cross sectional design. Children diagnosed with ILO (N = 70), chronic non-specific cough (N = 70), mild asthma (N = 60), or moderate to severe asthma (N = 60) were identified from the electronic medical record of a large children's hospital. Spirometry was completed before ILO, non-specific cough, or asthma diagnoses were made by pediatric laryngologists or pulmonologists. Spirometry was performed following American Thoracic Society guidelines and was interpreted by a pediatric pulmonologist. Forced Vital Capacity (FVC), Forced Expiratory Volume in 1 Second (FEV1), FEV1/FVC Ratio (FEV1/FVC), Forced Mid-Expiratory Flow 25--75 % (FEF25-75%), pulmonologist interpretation of flow volume loops, and overall exam findings were extracted from the medical record.

RESULTS

Ninety seven percent of children with ILO or chronic non-specific cough presented with spirometry values within normative range. Patients with ILO, non-specific cough, and mild asthma presented with FVC, FEV1, FEV1/FVC, and FEF25-75% values in statistically similar range. Children with moderate to severe asthma presented with significantly reduced FVC (p < .001), FEV1 (p < .001), FEV1/FVC (p < .001), and FEF25-75% (p < .001) values when compared with patients in the other groups. Flow volume loops were predominantly normal for children with ILO and non-specific cough.

CONCLUSIONS

Findings indicate that ILO and chronic non-specific cough can neither be diagnosed nor differentiated from mild asthma using spirometry alone. Spirometry should therefore be used judiciously with this population, bearing in mind the limitations of the procedure. Future research should determine the most effective and efficient ways of delineating ILO and non-specific cough from other respiratory conditions in children.

A speech therapy treatment protocol for exercise induced laryngeal obstruction

Background

Exercise induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems in young individuals, relevant to 5%-7% of young people. It is caused by paradoxical inspiratory adduction of laryngeal structures and diagnosed by continuous visualization of the larynx during high intensity exercise. Empirical data suggest that EILO consists of different subtypes that require different therapeutic approaches. Currently applied treatment approaches do not rest on randomized controlled trials (RCTs), and thus evidence-based guidelines cannot be established. This protocol describes the speech therapy treatment approach which is applied to EILO patients in a large prospective RCT called HelpILO.

Methods and analysis

Consenting patients consecutively diagnosed with EILO at Haukeland University Hospital are randomized into four treatment arms. Speech therapy is represented in two of these, provided in a structured manner based on general speech therapy principles and abdominal breathing, combined with experience obtained with these patients at our hospital during the last decades. The main outcome measure of HelpILO is changes of laryngoscopically visualized laryngeal adduction, rated at peak exercise before vs. after interventions, using a validated scoring system.

Ethics and dissemination

Despite widespread use of speech therapy in patients with EILO, this approach is insufficiently tested in RCTs, and the study is therefore considered ethically appropriate. The study will provide knowledge listed as a priority in a recent statement issued by major respiratory and laryngological societies and requested by clinicians and researchers engaged in this area. The results will be presented at relevant conferences, patient fora, and media platforms, and published in relevant peer reviewed international journals.

Dysfunctional Breathing in Children: A Literature Review

Dysfunctional breathing (DB) describes a respiratory condition that is mainly characterized by abnormal breathing patterns, affecting both children and adults, often leading to intermittent or chronic complaints and influencing physiological, psychological, and social aspects. Some symptoms include breathlessness; dizziness; palpitations; and anxiety, while its classification lies in breathing pattern disorders and upper airway involvement. Its prevalence among the pediatric population varies with a female overrepresentation, while the existence of comorbidities in DB, such as asthma, gastro-esophageal reflux, nasal diseases, and anxiety/depression, frequently leads to misdiagnosis or underdiagnosis and complicates therapeutic approaches. The basic diagnostic tools involve a detailed history, physical examination, and procedures such as structured light plethysmography, cardiopulmonary exercise testing, and laryngoscopy when a laryngeal obstruction is present. The management of DB presumes a multidimensional approach encompassing breathing retraining, disease-specific advice through speech and language therapy in the presence of laryngeal obstruction, psychotherapy for fostering self-efficacy, and surgical therapy in a structural abnormality. The current review was developed to provide a summary of classifications of DB and epidemiological data concerning the pediatric population, comorbidities, diagnostic tools, and therapeutic approaches to enhance the comprehension and management of DB in children.

Adult Laryngomalacia: A Scoping Review

OBJECTIVE

This review sought to determine the characteristics of adults diagnosed with new onset laryngomalacia including airway symptoms, laryngoscopic findings, treatments, and outcomes. Moreover, we wanted to highlight suspected limitations in the literature.

DATA SOURCES

Studies were identified through CINAHL, Cochrane Review, PubMed, and Scopus published between 1966 and 2023.

REVIEW METHODS

The search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis Extension for Scoping Reviews checklist by 2 independent investigators. A meta-analysis of proportions and continuous measures was conducted.

RESULTS

Of the 1121 abstracts identified, 33 articles pertaining to laryngomalacia in the adult population were included. The most common presenting symptoms were stridor at rest (78.3%, 65.1-88.3) and dyspnea with exertion (83.8%, 64.8-96.3). The most suspected etiology was exercise-induced (86.0%, 69.4-95.5), and the most common description of laryngomalacia on visualization was collapse of supraglottic structures during exercise (93.3%, 79.0-99.1). Nonsurgical options were attempted in 87.0% (54.0-99.1), which included oral appliances, respiratory retraining, breathing techniques, and working with a speech pathologist. Surgical options were ultimately performed in 84.2% (75.0-91.0). Complete resolution of symptoms following therapy was seen in 61.9% (48.0-74.6).

CONCLUSION

Adult onset laryngomalacia is difficult to characterize. It typically presents in patients during exercise, with neurological injury, or idiopathically. Surgical management can lead to improvement or complete resolution of symptoms. The need for a universal nomenclature is highlighted in this review, as it is inconsistently classified.

Evaluation and management of exercise-induced dyspnea in otherwise healthy adolescents and young adults: A critical review

Dyspnea on exertion in otherwise healthy adolescents and young adults is often brought to the attention of a pediatric pulmonologist when it interferes with an athletic activity. Assessment of the cause and management has been controversial. Skilled pediatric pulmonologists may suspect the cause from a careful history, but a more definite diagnosis is needed to provide the most appropriate management. Suspecting that laryngeal obstruction is the major cause, continuous laryngoscopy during exercise has been proposed. However, that method tends to over diagnose laryngeal obstruction and does not consider that the larynx is not the major cause of dyspnea on exertion (DOE). The cause of DOE can generally be best identified by a treadmill test using cardiopulmonary monitoring to determine the physiology associated with reproduced symptoms. Management of DOE requires a specific diagnosis and may involve medication, surgery, or education and training.

Feasibility of Constant Work Rate Testing to Detect Exercise-Induced Laryngeal Obstruction

INTRODUCTION

Exercise-induced laryngeal obstruction (EILO) is a condition in which laryngeal structures inappropriately obstruct the upper airway during exercise. The standard diagnostic test for EILO is the continuous laryngoscopy during exercise (CLE) test, usually performed with an incremental work rate protocol regardless of the nature of the triggering event. Typically, laryngeal obstruction occurs only briefly at the end of an incremental test, near peak work capacity. We aimed to investigate constant work rate (CWR) protocols for CLE testing to expand diagnostic test modalities and improve the understanding of EILO.

METHODS

In this prospective, self-controlled feasibility study, 10 patients with EILO performed both an incremental and a CWR CLE test at 70%, 80%, and 90% of maximal exercise capacity. Laryngoscopic video data were recorded and compared, and we evaluated the ability of CWR to reproduce the symptoms and laryngeal obstruction seen in incremental testing.

RESULTS

In 70%-90% of cases, CWR testing induced at least the same severity of obstruction as incremental testing and CLE scores remained comparable across test modalities. CWR at 70% allowed observation of laryngeal obstruction for a significantly longer duration than in incremental testing (158 s; 95% confidence interval, 25-291 s; P = 0.027). Dyspnea intensity appeared higher during CWR testing compared with incremental testing.

CONCLUSIONS

Submaximal CWR CLE testing is feasible and able to induce EILO equivalent to the standard incremental CLE test. This is the first step toward tailored CLE exercise protocols, and further studies are now needed to establish the utility of CWR in clinical and research settings.

Prevalence and characterisation of exercise-induced laryngeal obstruction in patients with exercise-induced dyspnoea

OBJECTIVE

The prevalence of exercise-induced laryngeal obstruction is largely unknown. This study aimed to evaluate the prevalence of this condition in a selected study population of patients with exercise-induced dyspnoea.

METHOD

A retrospective analysis was conducted of demographic data, co-morbidities, medication, symptoms, performance level of sporting activities, continuous laryngoscopy exercise test results and subsequent treatment.

RESULTS

Data from 184 patients were analysed. The overall prevalence of exercise-induced laryngeal obstruction in the study population was 40 per cent, and the highest prevalence was among females aged under 18 years (61 per cent). However, a high prevalence among males aged under 18 years (50 per cent) and among adults regardless of gender (34 per cent) was also found.

CONCLUSION

The prevalence of exercise-induced laryngeal obstruction is clinically relevant regardless of age and gender. Clinicians are encouraged to consider exercise-induced laryngeal obstruction as a possible diagnosis in patients suffering from exercise-induced respiratory symptoms. No single characteristic that can distinguish exercise-induced laryngeal obstruction from other similar conditions was identified.

Are Questionnaires Helpful To Predict Exercise-Induced Bronchoconstriction (EIB) And Exercise-Induced Laryngeal Obstruction (EILO)?

OBJECTIVE

Exercise induced laryngeal obstruction (EILO) is an important differential diagnosis to exercise induced bronchoconstriction (EIB) and diagnosed via continuous laryngoscopy while exercising (CLE). However, availability of CLE is limited to specialized centres. And without CLE EILO is often misdiagnosed as EIB. Therefore it is essential to carefully preselect potential EILO candidates. Aim of this study was to investigate whether two short questionnaires -Asthma Control Test (ACT) and Dyspnea Index (DI) evaluating upper airway-related dyspnea- can differentiate between EIB and EILO.

METHODS

Patients with dyspnea while exercising were analysed with an exercise challenge in the cold chamber (ECC) to diagnose EIB in visit 1 (V1), as appropriate a CLE in visit 2 (V2, 4-6 weeks after V1) and ACT and DI in V1 and V2. EIB patients were treated with asthma medication after V1.

RESULTS

Complete dataset of 36 subjects were gathered. The ACT showed lower values in V2 in EILO compared to EIB patients. A lack of improvement in ACT in V2 after asthma medication of EIB patients is suspicious for additional EILO diagnosis. The DI showed higher values in V1 in EILO compared to EIB patients. A score≥30 can predict a positive CLE reaction.

CONCLUSION

ACT and DI are valuable tools in preselecting CLE candidates to assure timely diagnostic despite limited diagnostic capabilities.

A multidimensional strategy to managing dysfunctional breathing and exercise-induced laryngeal obstruction in adolescent athletes

BACKGROUND

Exercise induced laryngeal obstruction (EILO) causes inspiratory distress in the upper airway in many adolescent athletes. The nature of EILO is not fully understood, and effective management strategies are lacking. This study aimed to assess the effectiveness of a multidimensional individually tailored intervention, including Norwegian Psychomotor Physiotherapy (NPMP), elements of cognitive behavioural therapy and a rehabilitation plan, in reducing inspiratory distress and dysfunctional breathing in adolescent athletes with EILO.

METHODS

A mixed methods design, which combined qualitative and quantitative research, was used. Data, including subjective experiences of respiratory distress, findings from body examinations and objective measurements of lung function and aerobic capacity were gathered before and after a five month intervention involving 18 participants.

RESULTS

Following the intervention, the participants showed a reduction in respiratory distress and anxiousness associated with their breathing difficulties. Furthermore, the participants reported to be more in control of their breathing. The body assessments revealed a more functional breathing motion and improved posture, which imply that the breathing was less thoracic and more diaphragmatic in rest and exercise in all participants after the intervention.

CONCLUSIONS

Our results suggest that a multidimensional individually tailored intervention, including NPMP based physiotherapy, cognitive behavioural therapy elements, and a rehabilitation plan may reduce inspiratory distress and dysfunctional breathing in athletes with EILO.

TRIAL REGISTRATION

ClinicalTrials.gov Protocol Registration and Results system NCT06033755, date of registration: September12, 2023. Retrospectively registered.

Upper airway assessment and its implications for interventions by respiratory physiotherapists

BACKGROUND

When noninvasive interventions such as chest physiotherapy fail, then more aggressive interventions for airway secretion clearance with nasotracheal airway suctioning may be required. Clinicians however have to insert the nasotracheal suction catheter "blindly" and the success of being able to trigger a cough and pass through the vocal folds with a suction catheter is low.

CASE DESCRIPTION

The patient, a 48-year-old male underwent a heart and lung transplant. Following extubation, the patient developed secretion retention with a weak ineffective cough and swallow and required physiotherapy interventions with frequent "blind" passes of nasotracheal suctioning.

OUTCOMES

The patient required nasotracheal suction with frequent multiple failed attempts before successful passage of the suction catheter to trigger a cough reflex and clear secretions. A combined physiotherapist and speech and language therapist intervention during fiberoptic endoscopic evaluation of swallow (FEES) was recorded to both evaluate swallow and passage of the suction catheter. The video illustrated the successful passage of a suctioning catheter through the vocal folds leading to an effective cough and airway clearance.

DISCUSSION

We present a case report demonstrating that it is feasible to visualize the upper airways during nasotracheal suctioning as an objective means to guide the more accurate successful insertion of the suction catheter past the vocal folds. Rather than "blind" placement of nasotracheal suction catheters visualization using transnasal laryngoscopy should be useful to increase chances of passing through the vocal folds.

The Clinical Utility of Continuous Laryngoscopy During Exercise: A Report of Two Cases

Exertional dyspnea is a common and disabling symptom in otherwise healthy children and adolescents, as well as in children with baseline airway abnormalities. It impairs the quality of life and may be associated with fatigue and underperformance in sports. Exertional dyspnea can be caused by a wide variety of structural and psychogenic causes. Exercise-induced laryngeal obstruction (EILO) is a relatively prevalent entity in young people that usually presents with exertional stridor, coughing, and dyspnea caused by transient closure of the larynx. In more complex cases where conventional tests such as pulmonary function tests (PFTs), chest imaging, ECG, and echocardiography are unrevealing, continuous laryngoscopy during exercise (CLE) tests may provide diagnostic utility. In addition to the baseline abnormalities visualized by conventional laryngoscopy, CLE can assess dynamic laryngeal responses during exercise. This article describes the clinical characteristics of two pediatric patients with various degrees of laryngeal dysfunction at baseline and the utility of CLE testing in tailoring management strategies.

A longitudinal follow-up of continuous laryngoscopy during exercise test scores in athletes irrespective of laryngeal obstruction, respiratory symptoms, and intervention

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) is diagnosed by the continuous laryngoscopy during exercise (CLE) test. Whether or how much CLE test scores vary over time is unknown. This study aimed to compare CLE test scores in athletes over time, irrespective of respiratory symptoms and grade of laryngeal obstruction.

METHODS

Ninety-eight athletes previously screened for EILO were invited for a follow-up CLE test irrespective of CLE scores and respiratory symptoms. Twenty-nine athletes aged 16-27 did a follow-up CLE test 3-23 months after the baseline test. Laryngeal obstruction at the glottic and supraglottic levels was graded by the observer during exercise, at baseline and follow-up, using a visual grade score (0-3 points).

RESULTS

At baseline, 11 (38%) of the 29 athletes had moderate laryngeal obstruction and received advice on breathing technique; among them, 8 (73%) reported exercise-induced dyspnea during the last 12 months. At follow-up, 8 (73%) of the athletes receiving advice on breathing technique had an unchanged supraglottic score. Three (17%) of the 18 athletes with no or mild laryngeal obstruction at baseline had moderate supraglottic obstruction at follow-up, and none of the 3 reported exercise-induced dyspnea.

CONCLUSIONS

In athletes with repeated testing, CLE scores remain mostly stable over 3-24 months even with advice on breathing technique to those with EILO. However, there is some intraindividual variability in CLE scores over time.

TRIAL REGISTRATION

ISRCTN, ISRCTN60543467, 2020/08/23, retrospectively registered, ISRCTN - ISRCTN60543467: Investigating conditions causing breathlessness in athletes.

Therapy Outcomes for Teenage Athletes With Exercise-Induced Laryngeal Obstruction

PURPOSE

This study examined treatment outcomes of speech-language pathology intervention addressing exercise-induced laryngeal obstruction (EILO) symptoms in teenage athletes.

METHOD

A prospective cohort design was utilized; teenagers diagnosed with EILO completed questionnaires during initial EILO evaluations, posttherapy, 3-month posttherapy, and 6-month posttherapy. Questionnaires examined the frequency of breathing problems, the use of the techniques taught in therapy, and the use of inhaler. Patients completed the Pediatric Quality of Life (PedsQL) inventory at all time points.

RESULTS

Fifty-nine patients completed baseline questionnaires. Of these, 38 were surveyed posttherapy, 32 at 3-month posttherapy, and 27 at 6-month posttherapy. Patients reported more frequent and complete activity participation immediately posttherapy (p = .017) as well as reduced inhaler use (p = .036). Patients also reported a significant reduction in the frequency of breathing problems 6-month posttherapy (p = .015). Baseline PedsQL physical and psychosocial scores were below normative range and were not impacted by therapy. Baseline physical PedsQL score significantly predicted frequency of breathing difficulty 6-month posttherapy (p = .04), as better baseline scores were associated with fewer residual symptoms.

CONCLUSIONS

Therapy with a speech-language pathologist for EILO allowed for more frequent physical activity following therapy completion and decreased dyspnea symptoms 6-month posttherapy. Therapy was associated with a decrease in inhaler use. PedsQL scores indicated mildly poor health-related quality of life even after EILO symptoms improved. Findings support therapy as an effective treatment for EILO in teenage athletes and suggest that dyspnea symptoms may continue to improve following discharge as patients continue using therapy techniques.

Prevalence and impact of exercise-induced laryngeal obstruction in asthma: a study protocol for a cross-sectional and longitudinal study

INTRODUCTION

Exercise-induced laryngeal obstruction (EILO) and exercise-induced asthma can cause troublesome respiratory symptoms that can be difficult to distinguish between. Further, there is now a growing appreciation that the two conditions may coexist, complicating the interpretation of symptoms. The primary aim of this study is to investigate the prevalence of EILO in patients with asthma. Secondary aims include evaluation of EILO treatment effects and investigation of comorbid conditions other than EILO in patients with asthma.

METHODS AND ANALYSIS

The study will be conducted at Haukeland University Hospital and Voss Hospital in Western Norway, and enrol 80-120 patients with asthma and a control group of 40 patients without asthma. Recruitment started in November 2020, and data sampling will continue until March 2024. Laryngeal function will be assessed at baseline and at a 1-year follow-up, using continuous laryngoscopy during high-intensity exercise (CLE). Immediately after the EILO diagnosis is verified, patients will be treated with standardised breathing advice guided by visual biofeedback from the laryngoscope video screen. The primary outcome will be the prevalence of EILO in patients with asthma and control participants. Secondary outcomes include changes in CLE scores, asthma-related quality of life, asthma control and number of the asthma exacerbations, as assessed between baseline and the 1-year follow-up.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Regional Committee for Medical and Health Research Ethics, Western Norway, (ID number 97615). All participants will provide signed informed consent before enrolment. The results will be presented in international journals and conferences.

TRIAL REGISTRATION NUMBER

NCT04593394.

Exercise induced laryngeal obstruction (EILO) in children and young people: Approaches to assessment and management

Exercise Induced Laryngeal Obstruction (EILO) is characterised by breathlessness, cough and/or noisy breathing particularly during high intensity exercise. EILO is a subcategory of inducible laryngeal obstruction where exercise is the trigger that provokes inappropriate transient glottic or supraglottic narrowing. It is a common condition affecting 5.7-7.5% of the general population and is a key differential diagnosis for young athletes presenting with exercise related dyspnoea where prevalence rates go as high as 34%. Although the condition has been recognised for a long time, little attention, and awareness of the condition results in many young people dropping out of sporting participation due to troublesome symptoms. With evolving understanding of the condition, diagnostic tests and interventions, this review looks to present the current available evidence and best practice when managing young people with EILO.

Diagnostic work-up of exercise-induced laryngeal obstruction

PURPOSE

Exercise-induced laryngeal obstruction (EILO) is suspected when dyspnea associated with upper airway symptoms is triggered by exercise. This condition affects mainly adolescent athletes. Visualization of the obstruction, while the patient is experiencing the symptoms during continuous laryngoscopy during exercise (CLE-test) is the gold standard for diagnosing EILO. Our study aims to evaluate the prevalence of EILO in a population presenting exercise-induced inspiratory symptoms (EIIS) or uncontrolled asthma with exertional symptoms. The second objective was to evaluate the diagnostic strength of laryngology consultation (LC) and pulmonary function tests (PFTs).

METHODS

All patients referred to our center for EIIS or uncontrolled asthma with exertional symptoms were included. EILO diagnosis was made if Maat score was > 2 for patients with CLE-test or if there were inspiratory anomalies on PFTs and LC. The sensitivity and specificity of LC and PFTs as diagnostic tools were calculated considering CLE-test as the gold standard.

RESULTS

Sixty two patients were referred to our center for EIIS or uncontrolled asthma with exertional symptoms. EILO was diagnosed in 28 patients (56%) with associated asthma in 9 patients (18%). The sensibility and specificity of LC for supraglottic anomalies were 75% and 60%, respectively. The sensibility and specificity of PFTs were 61% and 89%, respectively.

CONCLUSIONS

There was a high prevalence of EILO among patients with EIIS and uncontrolled asthma. Some clinical characteristics might guide the diagnosis. Nevertheless, CLE-test remained the gold standard for EILO diagnosis and identification of the dysfunctional upper airway site to provide specific management.

Identification of Breathing Pattern Disorder in Athletes With Exercise-Induced Laryngeal Obstruction: A Novel Assessment Tool

OBJECTIVE

To report the diagnostic utility of the novel, high-ventilatory task assessment tool called the Milstein Breathing Pattern Assessment Index (M-BPAI) for evaluation of Breathing Pattern Disorder (BPD) in athletes with and without breathing difficulty, and to evaluate the prevalence of BPD in athletes referred for Exercise Induced Laryngeal Obstruction (EILO). BPD is an abnormal respiratory biomechanical pattern caused from functional or structural factors. The presence of BPD in athletes with EILO is unknown. The current clinical evaluations of dysfunctional breathing patterns are limiting for evaluation of BPD in patients with EILO, as these only evaluate the patients in low ventilatory output tasks of rest breathing.

STUDY DESIGN AND METHODS

In this prospective study, a total of 77 athletes referred to the clinic for suspected EILO and 58 athletes without any respiratory difficulty underwent M-BPAI assessment. Data collection from the experimental group also included the Dyspnea Index, and laryngeal video endoscopic provocation test.

RESULTS

The M-BPAI score was significantly larger in the patient group compared to the control group. An overall M-BPAI score of ≥8 corresponds to the AUC of 0.87 (95% CI: 0.81-0.93) with a sensitivity of 0.862 and specificity of 0.792. A total of 60 (78%) patients had an overall M-BPAI score of ≥8.

CONCLUSION

The M-BPAI has the potential to be a valuable clinical diagnostic marker for identifying BPD in patients with suspected EILO with further research and validation.

Use of inhaled ipratropium bromide to improve exercise-induced laryngeal obstruction cannot be recommended

Introduction

Exercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems in young adults. Current management generally consists of breathing advice, speech therapy, inspiratory muscle training or supraglottoplasty in highly motivated subjects with supraglottic collapse. Inhaled ipratropium bromide (IB) is a muscarinic receptor antagonist used to treat asthma that is suggested in a few reports to improve EILO symptoms. The aim of the present study was to investigate effects of inhaled IB in EILO diagnosed by continuous laryngoscopy exercise (CLE) test and classified by CLE scores.

Methods

A randomised crossover trial was conducted at Haukeland University Hospital, Bergen, Norway, enrolling participants diagnosed with EILO defined by characteristic symptoms and CLE score ≥3 (range 0-12). Two consecutive CLE tests were performed within 2 weeks, one test with and one test without prior administration of inhaled IB in a randomised order. Main outcomes were the CLE score, dyspnoea measured using a modified BORG scale (range 0-10) and cardiopulmonary exercise data provided by the CLE test.

Results

20 participants (14 females) aged 12-25 years participated, and all ran to exhaustion on both tests. Mean CLE score, BORG score and peak oxygen consumption were similar in tests performed with and without IB; mean differences (95% confidence interval) were 0.08 (-0.28-0.43), 0.35 (-0.29-0.99) and -0.4 (-1.9-1.1) mL·kg^-1·min^-1, respectively.

Conclusion

Inhaled IB did not improve CLE score, dyspnoea or exercise capacity in subjects with EILO. The study does not support the use of inhaled IB to treat EILO.

The continuous laryngoscopy exercise test in severe or in difficult-to-treat asthma in adults: a systematic review

OBJECTIVE

A systematic review was performed to determine if the continuous laryngoscopy exercise test (CLE) has been used in the diagnostics of exercise dyspnea in adults with asthma, and whether inducible laryngeal obstruction (ILO) is found in those with asthma or with severe or difficult-to-treat asthma.

DATA SOURCES

We used Scopus and PubMed databases. The articles published up to 13 August 2019 were considered.

STUDY SELECTIONS

We excluded manuscripts that did not contain information about adult patients with asthma. We included six studies from 59 search results in Scopus and none from the 17 search results in PubMed.

RESULTS

The articles included 455 study individuals. Of these, 229 (50.3%) had diagnosed asthma or were treated with asthma medication. Altogether 31/229 (13.5%) subjects with diagnosis of asthma or previous asthma treatment had exercise-induced laryngeal obstruction (EILO) as comorbidity. The CLE test was performed on 229 patients with asthma. The method was used only for differential diagnosis of exercise-induced dyspnea to confirm EILO. At least 10/455 (2.2%) out of the 455 subjects experienced adverse events.

CONCLUSIONS

This systematic review revealed that only a small proportion of patients with asthma had undergone the CLE test to assess exercise-induced dyspnea. None of the selected manuscripts reported severity of asthma. Whether CLE provides a valuable diagnostic tool for patients with severe or difficult-to-treat asthma cannot be determined according to this review.

Vocal cord dysfunction/inducible laryngeal obstruction: novel diagnostics and therapeutics

INTRODUCTION

Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is an important medical condition but understanding of the condition is imperfect. It occurs in healthy people but often co-exists with asthma. Models of VCD/ILO pathophysiology highlight predisposing factors rather than specific mechanisms and disease expression varies between people, which is seldom appreciated. Diagnosis is often delayed, and the treatment is not evidence based.

AREAS COVERED

A unified pathophysiological model and disease phenotypes have been proposed. Diagnosis is conventionally made by laryngoscopy during inspiration with vocal cord narrowing >50% Recently, dynamic CT larynx was shown to have high specificity (>80%) with potential as a noninvasive, swift, and quantifiable diagnostic modality. Treatment entails laryngeal retraining with speech pathology intervention and experimental therapies such as botulinum toxin injection. Multidisciplinary team (MDT) clinics are a novel innovation with demonstrated benefits including accurate diagnosis, selection of appropriate treatment, and reductions in oral corticosteroid exposure.

EXPERT OPINION

Delayed diagnosis of VCD/ILO is pervasive, often leading to detrimental treatments. Phenotypes require validation and CT larynx can reduce the necessity for laryngoscopy, thereby fast-tracking diagnosis. MDT clinics can optimize management. Randomized controlled trials are essential to validate speech pathology intervention and other treatment modalities and to establish international standards of care.

Diagnosis and management of allergy and respiratory disorders in sport: An EAACI task force position paper

Allergy and respiratory disorders are common in young athletic individuals. In the context of elite sport, it is essential to secure an accurate diagnosis in order to optimize health and performance. It is also important, however, to consider the potential impact or consequences of these disorders, in recreationally active individuals engaging in structured exercise and/or physical activity to maintain health and well-being across the lifespan. This EAACI Task Force was therefore established, to develop an up-to-date, research-informed position paper, detailing the optimal approach to the diagnosis and management of common exercise-related allergic and respiratory conditions. The recommendations are informed by a multidisciplinary panel of experts including allergists, pulmonologists, physiologists and sports physicians. The report is structured as a concise, practically focussed document, incorporating diagnostic and treatment algorithms, to provide a source of reference to aid clinical decision-making. Throughout, we signpost relevant learning resources to consolidate knowledge and understanding and conclude by highlighting future research priorities and unmet needs.

Adjustments of non-invasive ventilation and mechanically assisted cough by combining ultrasound imaging of the larynx with transnasal fibre-optic laryngoscopy: a protocol for an experimental study

INTRODUCTION

Application of non-invasive positive airway pressure may provoke laryngeal responses that obstruct the airways, especially in patients with disturbed laryngeal control. To control and adjust for this, transnasal fibre-optic laryngoscopy (TFL) is used to visualise laryngeal movements during therapeutic interventions. Being an invasive procedure, this may be unpleasant for patients. The aim of this study is to evaluate if ultrasound (US) imaging of the larynx may be used as an alternative less invasive diagnostic tool for evaluating the upper airway responses to non-invasive ventilation (NIV) and mechanical insufflation-exsufflation (MI-E).

METHODS AND ANALYSIS

This protocol presents an experimental cross-sectional study of a novel method to study laryngeal responses in adult healthy volunteers (n=30). The participants will be assessed with simultaneous TFL and laryngeal US imaging (anterior and lateral approaches) during NIV and MI-E therapy. Additionally, airflow and pressure signals will be registered during the procedures. The primary outcome is whether laryngeal US is a feasible method to study laryngeal responses and, if so, to compare the laryngeal responses visualised with TFL and US. The participants' perception of the examinations will be recorded. Secondary outcomes include airflow curve shapes and calculated ventilation volumes during the interventions.

ETHICS AND DISSEMINATION

The study has been approved by The Regional Committee for Medical Research Ethics in Norway, and registered in ClinicalTrials.gov. Results will be disseminated through peer-reviewed journals, presentation of scientific abstracts at international medical conventions and oral presentations in relevant medical conventions.

TRIAL REGISTRATION NUMBER

NCT04586855.

Exercise-induced laryngeal obstruction (EILO) in athletes: a narrative review by a subgroup of the IOC Consensus on 'acute respiratory illness in the athlete'

Exercise-induced laryngeal obstruction (EILO) is caused by paradoxical inspiratory adduction of laryngeal structures during exercise. EILO is an important cause of upper airway dysfunction in young individuals and athletes, can impair exercise performance and mimic lower airway dysfunction, such as asthma and/or exercise-induced bronchoconstriction. Over the past two decades, there has been considerable progress in the recognition and assessment of EILO in sports medicine. EILO is a highly prevalent cause of unexplained dyspnoea and wheeze in athletes. The preferred diagnostic approach is continuous visualisation of the larynx (via laryngoscopy) during high-intensity exercise. Recent data suggest that EILO consists of different subtypes, possibly caused via different mechanisms. Several therapeutic interventions for EILO are now in widespread use, but to date, no randomised clinical trials have been performed to assess their efficacy or inform robust management strategies. The aim of this review is to provide a state-of-the-art overview of EILO and guidance for clinicians evaluating and treating suspected cases of EILO in athletes. Specifically, this review examines the pathophysiology of EILO, outlines a diagnostic approach and presents current therapeutic algorithms. The key unmet needs and future priorities for research in this area are also covered.

Reliability of trans-laryngeal airway resistance measurements during maximal exercise

Objective

: Exercised induced laryngeal obstruction (EILO) is an important cause of exertional dyspnea. The diagnosis rests on visual judgement of relative changes of the laryngeal inlet during continuous laryngoscopy exercise (CLE) tests, but we lack objective measures that reflect functional consequences. We aimed to investigate repeatability and normal values of trans-laryngeal airway resistance measured at maximal intensity exercise.

Methods

: Thirty-one healthy non-smokers without exercise related breathing problems were recruited. Participants performed two CLE tests enabling verified positioning of two pressure sensors, one at the tip of the epiglottis (supraglottic) and one by the fifth tracheal ring (subglottic). Airway pressure and flow data were continuously collected breath-by-breath and used to calculate trans-laryngeal resistance at peak exercise. Laryngeal obstruction was assessed according to a standardised CLE-score system.

Results

: Data from 26 participants (16 females) with two successful tests and equal CLE scores on both test-sessions were included in the trans-laryngeal resistance repeatability analyses. The coefficient of repeatability (CR) was 0.62 cmH2O·L−1·s−1, corresponding to a CR% of 21%. Mean (sd) trans-laryngeal airway resistance (cmH2O·L−1·s−1) in participants with no laryngeal obstruction (n=15) was 2.88 (0.50) in females and 2.18 (0.50) in males. Higher CLE scores correlated with higher trans-laryngeal resistance in females (r=0.81, p<0.001).

Conclusions

: This study establishes trans-laryngeal airway resistance obtained during exercise as a reliable parameter in respiratory medicine, opening the door for more informed treatment decisions and future research on the role of the larynx in health and disease.

Conundrums in the breathless athlete; exercise induced laryngeal obstruction or asthma?

PURPOSE

Exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO) are two disorders commonly considered when athletes complain of exertional dyspnea. They are highly different but often confused. We aimed to address this diagnostic challenge and its consequences in elite athletes.

METHODS

We included all athletes competing at national or international level, referred to our institution for workup for EILO during 2013-2016. We diagnosed EILO from video-recorded laryngoscopy performed during maximal cardiopulmonary treadmill exercise (CLE-test). Symptoms and previous diagnostic evaluations were obtained from referral letters and chart reviews.

RESULTS

EILO was diagnosed in 73/101 referred athletes, of whom 70/73 had moderate/severe supraglottic obstruction and 3/73 had primarily glottic obstruction with only minor supraglottic involvement. Of the 73 athletes with EILO, we were able to identify objective tests for asthma in 55 participants, of whom 22 had findings supporting asthma. However, 58/73 had used asthma therapy at some time previously, with current use in 28. Only three reported that asthma medication had improved their exercise related breathing problems, two of whom with tests confirming asthma. Treatment for EILO improved breathing problems in all but four.

CONCLUSIONS

Objective testing verified EILO in most of the referred athletes. EILO coexisting with asthma was common, and large proportions had used asthma medication; however, few reported effect on exercise related breathing problems. Unexplained persistent exertional dyspnoea must not lead to indiscriminate escalation of asthma treatment, but instead incite investigation for EILO, either as a co-morbidity or as a differential diagnosis.

Evaluating Children and Adolescents with Suspected Exercise Induced Asthma: Real Life Data

OBJECTIVE

Exercise-induced bronchoconstriction (EIB) occurs frequently in children and adolescents and may be a sign of insufficient asthma control. EIB is often evaluated by respiratory symptoms, spirometry, eNO measurement and methacholine testing (MCT) instead of time consuming exercise test. Aim of this study was to analyse the amount of patients for which an exercise challenge in a cold chamber (ECC) was needed for a clear EIB diagnosis, to characterize EIB phenotypes and the incidence of exercise induced laryngeal obstruction (EILO) in a large cohort of patients with EIB.

METHODS

A retrospective analysis was performed in 595 children and adolescents (mean age 12.1 years) with suspected EIB from January 2014 to December 2018. Complete data sets of skin prick test, spirometry, eNO and MCT were available from 336 patients.

RESULTS

An ECC to confirm the EIB diagnosis was performed in 125 (37.2%) of patients. Three EIB phenotypes were detected: group 1: EIB without allergic sensitization (n=159); group 2: EIB with other than house dust mite (HDM) sensitization (n=87) and group 3: EIB with HDM sensitization (n=90). MCT and eNO showed significant differences between the subgroups: An eNO>46 ppb and/or a MCT<0.1 mg was found in 23.9% vs. 50.6% vs. 57.8% in group 1-3, respectively. Significantly more patients suffered from EILO in group 1 compared to group 2 and 3 (n=13 vs. n=1).

CONCLUSION

EIB without sensitization is as often as EIB with sensitization. In patients without sensitization, EILO has to be considered as a possible cause of symptoms during exercise.

Exercise-induced Laryngeal Obstruction: Protocol for a Randomized Controlled Treatment Trial

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathing problems in young individuals, caused by paradoxical inspiratory adduction of laryngeal structures, and diagnosed by continuous visualization of the larynx during high-intensity exercise. Empirical data suggest that EILO consists of different subtypes, possibly requiring different therapeutic approaches. Currently applied treatments do not rest on randomized controlled trials, and international guidelines based on good evidence can therefore not be established. This study aims to provide evidence-based information on treatment schemes commonly applied in patients with EILO.

METHODS AND ANALYSIS

Consenting patients consecutively diagnosed with EILO at Haukeland University Hospital will be randomized into four non-invasive treatment arms, based on promising reports from non-randomized studies: (A) standardized information and breathing advice only (IBA), (B) IBA plus inspiratory muscle training, (C) IBA plus speech therapy, and (D) IBA plus inspiratory muscle training and speech therapy. Differential effects in predefined EILO subtypes will be addressed. Patients failing the non-invasive approach and otherwise qualifying for surgical treatment by current department policy will be considered for randomization into (E) standard or (F) minimally invasive laser supraglottoplasty or (G) no surgery. Power calculations are based on the main outcomes, laryngeal adduction during peak exercise, rated by a validated scoring system before and after the interventions.

ETHICS AND DISSEMINATION

The study will assess approaches to EILO treatments that despite widespread use, are insufficiently tested in structured, verifiable, randomized, controlled studies, and is therefore considered ethically sound. The study will provide knowledge listed as a priority in a recent statement issued by the European Respiratory Society, requested by clinicians and researchers engaged in this area, and relevant to 5-7% of young people. Dissemination will occur in peer-reviewed journals, at relevant media platforms and conferences, and by engaging with patient organizations and the healthcare bureaucracy.

Clinical responses following inspiratory muscle training in exercise-induced laryngeal obstruction

Purpose

Exercise-induced laryngeal obstruction (EILO) is relatively common in young people. Treatment rests on poor evidence; however, inspiratory muscle training (IMT) has been proposed a promising strategy. We aimed to assess laryngeal outcomes shortly after IMT, and to compare self-reported symptoms with a control group 4–6 years later.

Methods

Two groups were retrospectively identified from the EILO-register at Haukeland University Hospital, Norway; one group had received only information and breathing advice (IBA), and another additionally IMT (IBA + IMT). At diagnosis, all participants performed continuous laryngoscopy during exercise (CLE), with findings split by glottic and supraglottic scores, and completed a questionnaire mapping exercise-related symptoms. After 2–4 weeks, the IBA + IMT-group was re-evaluated with CLE-test. After 4–6 years, both groups were re-assessed with a questionnaire.

Results

We identified 116 eligible patients from the EILO-register. Response rates after 4–6 years were 23/58 (40%) and 32/58 (55%) in the IBA and IBA + IMT-group, respectively. At diagnosis, both groups rated symptoms similarly, but laryngeal scores were higher in the IBA + IMT-group (P = 0.003). After 2–4 weeks, 23/32 in the IBA + IMT-group reported symptom improvements, associated with a decrease of mainly glottic scores (1.7–0.3; P < 0.001), contrasting unchanged scores in the 9/32 without symptom improvements. After 4–6 years, exercise-related symptoms and activity levels had decreased to similar levels in both groups, with no added benefit from IMT; however, full symptom resolution was reported by only 8/55 participants.

Conclusion

Self-reported EILO symptoms had improved after 4–6 years, irrespective of initial treatment. Full symptom resolution was rare, suggesting individual follow-up should be offered.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-07214-5.

Athlete Preparticipation Physical Evaluation

Preparticipation evaluations (PPE) are both a traditional and legal requirement by many governing bodies for sport. The ideal goal of the PPE is safe participation in sport for athletes. This article provides an overview of common PPE elements and current best practice recommendations. Descriptions of every possible examination are published elsewhere and are beyond the intent of this article. Additional considerations for transgender, masters athletes, and Special Olympians are also outside the scope of this review, but are well covered in The Preparticipation Physical Evaluation, fifth edition monograph.

Breathing patterns in people with exercise-induced laryngeal obstruction

Exercise-induced laryngeal obstruction (EILO) is common, but we lack readily available diagnostic tools. The larynx represents an important point of resistance in the airways, and we therefore hypothesized that EILO is associated with characteristic breathing patterns possible to record from a standard incremental ergospirometry test. We studied 24 individuals with moderate/severe EILO and 20 individuals with no-EILO, mean (SD) age 17 (6.1) and 24 (6.4) years, respectively. EILO versus no-EILO was verified from maximal continuous laryngoscopy treadmill exercise (CLE) tests, which also included ergospirometry. We described the relationships between minute ventilation ( V ˙ E ) versus tidal volume (VT ) and V ˙ E versus carbon dioxide output ( V ˙ CO 2 ), using respectively quadratic and linear equations, and applied adjusted regression models to compare ergospirometry data and curve parameters. Compared to the no-EILO group, the group with EILO had prolonged inspiratory time (Tin ), lower breathing frequency (Bf ), lower V ˙ E , and lower inspiratory flow rate ( V ˙ in ) at peak exercise. Mathematical modeling of the breathing pattern relationships was feasible in both groups, with similar coefficients of variation. For V ˙ E versus VT , the mathematical curve parameters were similar. For V ˙ E versus V ˙ CO 2 , the slope was similar but the intercept was lower in the EILO group. EILO was associated with prolonged Tin , lower Bf , V ˙ E , and V ˙ E . The relationship between V ˙ E versus VT was similar, whereas for V ˙ E versus V ˙ CO 2 , the slope was almost parallel but shifted downward for the EILO group. Most ergospirometry data overlapped, except V ˙ in which discriminated between EILO and no-EILO in a promising way.

Die induzierbare laryngeale Obstruktion (ILO) – Ursachen, klinische Präsentation, Diagnostik und Therapie

Wiederholt episodenhaft auftretende Atemnot ist im Kindes- und Jugendalter ein häufiges Symptom. Neben anstrengungsinduzierter Bronchialobstruktion im Rahmen eines Asthma bronchiale ist eine funktionelle Genese eine sehr häufige Differenzialdiagnose. Dennoch wird diese Diagnose häufig nicht oder mit langer Latenz gestellt. Unter dem Oberbegriff „ILO“ („inducible laryngeal obstruction“) werden sowohl funktionelle supraglottische Obstruktionen durch Kollaps der Knorpelstrukturen als auch Dysfunktionen auf Glottisebene wie „vocal cord dysfunction“ (VCD) subsumiert. Körperliche Anstrengung ist ein häufiger Auslöser; es werden jedoch auch Beschwerdebilder ohne Anstrengungsbezug beobachtet. Es wird der Erkenntnisstand zur Pathophysiologie referiert und die klinische Präsentation beschrieben. Ein wesentlicher Fokus des Artikels liegt im Folgenden auf der Darstellung eines sinnvollen und Ressourcen-orientierten diagnostischen Vorgehens. Der CLE-Test („continuous laryngoscopy exercise test“) als Provokationsmethode unter Wach-Videolaryngoskopie ist der Goldstandard, jedoch wird diese Diagnostik im deutschsprachigen Raum nicht flächendeckend vorgehalten. Dieses Positionspapier stellt daher die diagnostische Wertigkeit verschiedener anderer Diagnostik-Algorithmen und anamnestischer Informationen heraus. Ein weiterer Schwerpunkt des Papiers besteht in der detaillierten Vorstellung geeigneter atemphysiotherapeutischer Interventionen.

Development and validation of the Exercise-Induced Laryngeal Obstruction Dyspnea Index (EILODI)

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) causes exertional dyspnea and is important for its effect on quality of life, diagnostic confusion with exercise-induced asthma, and health care resource utilization. There is no validated patient-reported outcome measure specific to EILO.

OBJECTIVE

We sought to develop, validate, and define a minimal clinically important difference for a patient-reported outcome measure to be used with adolescents and young adults with EILO.

METHODS

A multidisciplinary group created a preliminary measure, modified by a 10-member participant focus group, with 20 items scored along a 5-point Likert scale. A subsequent cohort of participants recruited from a clinic, aged 12 to 21 years, with confirmed EILO by continuous laryngoscopy during exercise testing (1) completed the measure at 3 points in time over 28 days and (2) provided anchoring data in the form of a daily exercise log and categorical self-assessments of clinical improvement. Thirty additional participants without exertional dyspnea served as controls.

RESULTS

Two hundred nineteen subjects with mild to severe EILO participated in the exploratory factor analysis, which identified 7 factors within the preliminary outcome measure. After a process of item reduction, a 12-item metric with a total score ranging from 0 to 48 was developed. Mean scores of patients with EILO and healthy controls at baseline were 28.8 ± 7.4 and 4.5 ± 7.4, respectively. A minimal clinically important difference of 6 was determined by comparison of index change with changes in categorical self-assessments of improvement.

CONCLUSIONS

This is the first patient-reported outcome measure specifically designed for adolescents and young adults with EILO.

Exercise laryngoscopy in athletes and sportsmen: an easy way to assess exercise-induced laryngeal obstruction

BACKGROUND

Exercise-induced laryngeal obstruction (EILO) is an exercise-dependent dyspnoea, linked to a laryngeal closure during physical effort. It may concern from 5% to 7% of adolescents and young athletic adults. EILO is a quite recently described condition: standardized diagnostic criteria and consensual management are still to come. Formal diagnosis of EILO requires a continuous laryngoscopy during exercise (CLE). This test allows visualization of laryngeal abnormalities during an effort but is only accessible in specialized centres.

AIMS

We wanted to assess performance of a simplified CLE (sCLE) procedure for EILO diagnosis in everyday practice.

MATERIAL AND METHODS

The procedure consisted in a continuous flexible videolaryngoscopy during a cycloergometre cardio-pulmonary exercise test. Screening questionnaire and visual scoring of laryngeal abnormalities were performed. Patients clinically suspected of EILO were included from 2018 to 2020.

RESULTS

Seventeen consecutive subjects had an indication for sCLE. Fifteen patients underwent sCLE, and EILO-linked significative abnormalities were observed in 80% of them, thus confirming the diagnosis.

CONCLUSIONS

CLE can be done successfully in a simple way. Due to its simplicity, tolerance and contribution in EILO diagnosis, this simplified version of CLE may promote its widespread use in ENT and pulmonology practices, as an affordable confirmation test.

Characteristics and impact of exercise-induced laryngeal obstruction: an international perspective

Background

Exercise-induced laryngeal obstruction (EILO) is a common cause of exertional breathlessness and wheeze yet is frequently misdiagnosed as asthma. Insight regarding the demographic characteristics, laryngeal abnormalities and impact of EILO is currently limited, with data only available from individual centre reports. The aim of this work was to provide a broader perspective from a collaboration between multiple international expert centres.

Methods

Five geographically distinct clinical paediatric and adult centres (3 Denmark, 1 UK, 1 USA) with an expertise in assessing unexplained exertional breathlessness completed database entry of key characteristic features for all cases referred with suspected EILO over a 5-year period. All included cases completed clinical asthma workup and continuous laryngoscopy during exercise (CLE) testing for EILO.

Results

Data were available for 1007 individuals (n=713 female (71%)) with a median (range) age of 24 (8–76) years, and of these 586 (58%) were diagnosed with EILO. In all centres, EILO was frequently misdiagnosed as asthma; on average there was a 2-year delay to diagnosis of EILO, and current asthma medication was discontinued in 20%. Collapse at the supraglottic level was seen in 60%, whereas vocal cord dysfunction (VCD) was only detected/visualised in 18%. Nearly half (45%) of individuals with EILO were active participants in recreational-level sports, suggesting that EILO is not simply confined to competitive/elite athletes.

Conclusion

Our findings indicate that key clinical characteristics and the impact of EILO/VCD are similar in globally distinct regions, facilitating improved awareness of this condition to enhance recognition and avoid erroneous asthma treatment.

Exercise-induced laryngeal obstruction is a prevalent cause of exertional breathlessness and wheeze. In this international multicentre collaboration, 1007 patients waited, on average, 2 years for diagnosis and 20% were mistreated as asthmatic.https://bit.ly/3auXpcp

High Prevalence of Exercise-induced Laryngeal Obstruction in a Cohort of Elite Cross-country Skiers

INTRODUCTION

Exercise-induced laryngeal obstruction (EILO) is a differential diagnosis for asthma and prevalent in athletes referred for exercise-induced dyspnea. The aim of this study was to estimate the prevalence of EILO in elite cross-country skiers, known for a high prevalence of asthma.

METHOD

Elite cross-country skiers were invited for screening of EILO. Screening consisted of clinical assessment, questionnaires, skin prick test, spirometry, eucapnic voluntary hyperventilation test, and continuous laryngoscopy during exercise test. Current asthma was defined as physician-diagnosed asthma and use of asthma medication during the last 12 months. EILO was defined as ≥2 points at the supraglottic or glottic level during exercise at maximal effort, using a visual grade score system.

RESULT

A total of 89 (51% female) cross-country skiers completed the study. EILO was identified in 27% of the skiers, 83% of whom were female. All skiers with EILO had supraglottic EILO, and there was no glottic EILO. Current asthma was present in 34 (38%) of the skiers, 10 (29%) of whom had concomitant EILO. In the skiers with EILO, a higher proportion reported wheeze or shortness of breath after exercise, compared with skiers without EILO. In skiers with EILO and current asthma, compared with skiers with asthma only, a higher proportion reported wheeze or shortness of breath after exercise. Asthma medication usage did not differ between these groups.

CONCLUSION

EILO is common in elite cross-country skiers, especially females. Asthma and EILO may coexist, and the prevalence of respiratory symptoms is higher in skiers with both. Testing for EILO should be considered in cross-country skiers with respiratory symptoms.

Exercise-induced laryngeal obstruction: From clinical examination to continuous laryngoscopy during exercise

The diagnosis of exercise-induced laryngeal obstruction (EILO) should be suspected when exercise triggers inspiratory stridor. EILO is common in adolescent populations and has a significant impact on sports. Identification of laryngeal obstruction during continuous laryngoscopy during exercise (CLE) is the gold standard diagnostic tool for this disorder, which is not widely known in France. The challenge faced by otolaryngologists is to identify, among patients referred by pulmonologists or sports physicians, those with exercise-induced inspiratory symptoms or poorly controlled exercise-induced asthma, in whom a diagnosis of EILO is strongly suspected. Laryngoscopy at rest may reveal a laryngeal, glottic or supraglottic abnormality predictive of obstruction at increased inspiratory airflow. When pulmonary function tests are normal or in the case of failure of treatment of exercise-induced asthma, the otolaryngologist must complete the examination by a CLE test to confirm the diagnosis of EILO and identify the site of obstruction. This examination is well tolerated, minimally invasive and allows identification of the site of airflow obstruction, allowing specific conservative or surgical treatment. This technical note describes in detail clinical examination and CLE testing in patients with suspected EILO.

Reliability of maximum oxygen uptake in cardiopulmonary exercise testing with continuous laryngoscopy

Aims

A cardiopulmonary exercise test (CPET) is the gold standard to evaluate symptom-limiting exercise intolerance, while continuous laryngoscopy performed during exercise (CLE) is required to diagnose exercise-induced laryngeal obstruction. Combining CPET with CLE would save time and resources; however, the CPET data may be distorted by the extra equipment. We therefore aimed to study whether CPET with CLE influences peak oxygen uptake (V′_O2peak) and other gas exchange parameters when compared to a regular CPET.

Methods

Forty healthy athletes without exercise-related breathing problems, 15–35 years of age, performed CPET to peak exercise with and without an added CLE set-up, in randomised order 2–4 days apart, applying an identical computerised treadmill protocol.

Results

At peak exercise, the mean difference (95% confidence interval) between CPET with and without extra CLE set-up for V′_O2peak, respiratory exchange ratio (RER), minute ventilation (V′_E) and heart rate (HR) was 0.2 (−0.4 to 0.8) mL·kg⁻¹·min⁻¹, 0.01(−0.007 to 0.027) units, 2.6 (−1.3 to 6.5) L·min⁻¹ and 1.4 (−0.8 to 3.5) beats·min⁻¹, respectively. Agreement (95% limits of agreement) for V′_O2peak, RER and V′_E was 0.2 (±3.7) mL·kg⁻¹·min⁻¹, 0.01 (±0.10) units and 2.6 (±24.0) L·min⁻¹, respectively. No systematic or proportional bias was found except for the completed distance, which was 49 m (95% CI 16 to 82 m) longer during CPET.

Conclusion

Parameters of gas exchange, including V′_O2peak and RER, obtained from a maximal CPET performed with the extra CLE set-up can be used interchangeably with data obtained from standard CPET, thus preventing unnecessary additional testing.

Cardiopulmonary exercise testing (CPET) with concurrent continuous laryngoscopy provides reliable measures for maximal oxygen consumption and other CPET datahttps://bit.ly/36wVJhb

Changes in pulmonary function and feasibility of portable continuous laryngoscopy during maximal uphill running

Objective

To evaluate changes in pulmonary function and feasibility of portable continuous laryngoscopy during maximal uphill running.

Methods

Healthy volunteers participated in an uphill race. Forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) were obtained before and 5 and 10 min after finishing the race. Capillary blood lactate concentration ([BLa^-]) and Borg score for perceived exertion were registered immediately after the race. One participant wore a portable video-laryngoscope during the race, and the video was assessed for technical performance.

Results

Twenty adult subjects participated with a mean (SD) age of 40.2 (9.7) years. Mean (SD) race duration and post-exercise [BLa^-] was 13.9 (2.3) min and 10.7 (2.1) mmol/L, respectively, and the median (range) Borg score for perceived exertion was 9 (5–10).

Mean percentage change (95% CI) 5 and 10 min post-exercise in FEV₁ were 6.9 (3.7 to 10.2) % and 5.9 (2.7 to 9.0) %, respectively, and in FVC 5.2 (2.3 to 8.1) % and 4.7 (1.6 to 7.9) %, respectively. The recorded video of the larynx was of good quality.

Conclusions

Maximal aerobic field exercise induced bronchodilatation in the majority of the healthy non-asthmatic participants. It is feasible to perform continuous video-laryngoscopy during heavy uphill exercise.

Exercise Related Respiratory Problems in the Young-Is It Exercise-Induced Bronchoconstriction or Laryngeal Obstruction?

Complaints of breathlessness during heavy exercise is common in children and adolescents, and represent expressions of a subjective feeling that may be difficult to verify and to link with specific diagnoses through objective tests. Exercise-induced asthma and exercise-induced laryngeal obstruction are two common medical causes of breathing difficulities in children and adolescents that can be challenging to distinguish between, based only on the complaints presented by patients. However, by applying a systematic clinical approach that includes rational use of tests, both conditions can usually be diagnosed reliably. In this invited mini-review, we suggest an approach we find feasible in our everyday clinical work.

Self-Reported Health in Adolescents With Exercise-Induced Laryngeal Obstruction; A Cross-Sectional Study

Background: Exercise-induced laryngeal obstruction (EILO) is common in young people with exertional breathing difficulties. Psychological characteristics have been proposed as underlying contributors; however, the evidence for this is limited. Objectives: Describe self-reported health, self-efficacy, and anxiety symptoms in adolescents with EILO, and address possible associations with EILO subtypes and severity. Methods: Cross-sectional study of 71/180 (39%) adolescents tested for EILO at Haukeland University Hospital during 2014-2016, age range 14-18 years. Validated questionnaires were used to assess general self-rated health, subjective health complaints (Health Behavior in School-aged Children-Symptom Check List; HBSC-SCL), general self-efficacy (GSE), and anxiety symptoms (SCARED). The outcomes were compared with normative data from comparable unselected populations. Results: The HBSC-SCL items for somatic complaints revealed weekly or more often occurrence of headache in 42%, abdominal pain in 30%, backache in 31%, and dizziness in 32%. For psychological complaints, corresponding figures were 26% for feeling low, 43% for irritability or bad mood, 33% for feeling nervous, and 38% for sleep problems. Mean (range) GSE score was 3.13 (2.2-4.0), and reports suggesting anxiety symptoms were rare. The outcomes were in line with normative data from comparable unselected populations. Self-rated health, and scores obtained for HBSC-SCL, GSE, and SCARED were similarly distributed across EILO subtypes and severity. Conclusion: Self-reported health, self-efficacy, and level of anxiety symptoms in adolescents with laryngoscopically confirmed EILO were similar to data obtained in comparable unselected populations, irrespective of EILO subtype and severity. The findings challenge the notion that pediatric EILO is causally related to psychological problems.

Life-threatening laryngeal injury in Elite Rugby Union: Prevention and management laryngeal trauma in rugby

Laryngeal trauma is a life-threatening injury in contact sports. Due to its potentially devastating consequences, the prevention, diagnosis, and management of neck trauma both pitch side and at the hospital are essential for athletes.

The Need for Testing-The Exercise Challenge Test to Disentangle Causes of Childhood Exertional Dyspnea

Exertional dyspnea is a common symptom in childhood which can induce avoidance of physical activity, aggravating the original symptom. Common causes of exertional dyspnea are exercise induced bronchoconstriction (EIB), dysfunctional breathing, physical deconditioning and the sensation of dyspnea when reaching the physiological limit. These causes frequently coexist, trigger one another and have overlapping symptoms, which can impede diagnoses and treatment. In the majority of children with exertional dyspnea, EIB is not the cause of symptoms, and in asthmatic children it is often not the only cause. An exercise challenge test (ECT) is a highly specific tool to diagnose EIB and asthma in children. Sensitivity can be increased by simulating real-life environmental circumstances where symptoms occur, such as environmental factors and exercise modality. An ECT reflects daily life symptoms and impairment, and can in an enjoyable way disentangle common causes of exertional dyspnea.

High prevalence of exercise-induced stridor during Parkrun: a cross-sectional field-based evaluation

BACKGROUND AND OBJECTIVE

The differential diagnosis for exercise-associated breathlessness is broad, however, when a young athletic individual presents with respiratory symptoms, they are most often prescribed inhaler therapy for presumed exercise-induced asthma (EIA). The purpose of this study was therefore to use a novel sound-based approach to assessment to evaluate the prevalence of exertional respiratory symptoms and characterise abnormal breathing sounds in a large cohort of recreationally active individuals.

METHODS

Cross-sectional field-based evaluation of individuals completing Parkrun. PHASE 1: Prerace, clinical assessment and baseline spirometry were conducted. At peak exercise and immediately postrace, breathing was monitored continuously using a smartphone. Recordings were analysed retrospectively and coded for signs of the predominant respiratory noise. PHASE 2: A subpopulation that reported symptoms with at least one audible sign of respiratory dysfunction was randomly selected and invited to attend the laboratory on a separate occasion to undergo objective clinical workup to confirm or refute EIA.

RESULTS

Forty-eight participants (22.6%) had at least one audible sign of respiratory dysfunction; inspiratory stridor (9.9%), expiratory wheeze (3.3%), combined stridor+wheeze (3.3%), cough (6.1%). Over one-third of the cohort (38.2%) were classified as symptomatic. Ten individuals attended a follow-up appointment, however, only one had objective evidence of EIA.

CONCLUSIONS

The most common audible sign, detected in approximately 1 in 10 individuals, was inspiratory stridor, a characteristic feature of upper airway closure occurring during exercise. Further work is now required to further validate the precision and feasibility of this diagnostic approach in cohorts reporting exertional breathing difficulty.

Can Ultrasound Identify Paradoxical Vocal Fold Movement? A Pilot Study

OBJECTIVE

Vocal cord dysfunction (VCD) is characterized by paradoxical vocal fold movement (PVFM) during inspiration. The aim of this study was to determine whether ultrasound could accurately differentiate between normal and PVFM during respirations in a resting state.

DESIGN

Prospective, single-subject design.

SETTING

Academic medical center.

PATIENTS

A speech-language pathologist who was able to volitionally alternate between normal and PVFM when breathing at rest was recruited to participate in the study.

INTERVENTIONS

The subject was instructed to randomly alternate between normal and PVFM 20 times (10 times each). A single investigator imaged the vocal folds using ultrasound and reported when the subject alternated between the 2 respiratory states.

MAIN OUTCOME MEASURES

The subject recorded when they changed between the 2 respiratory states, whether the investigator identified with the change occurred, and if the correct respiratory state was identified.

RESULTS

The investigator recognized when the subject changed respiratory states and correctly identified the new respiratory state 100% of the time.

CONCLUSIONS

The findings of the current study were promising and suggest that ultrasound may have utility in the diagnosis of VCD. However, because of the preliminary nature of these results, further research is required before recommending its clinical implementation.

Exercise-Associated Dyspnea and Stridor: Thinking Beyond Asthma

Breathlessness during sport can be caused by various cardiorespiratory conditions, but when associated with stridor, usually arises from an upper airway etiology. The term exercise-induced laryngeal obstruction (EILO) is now used to describe the phenomenon of transient glottic closure occurring in association with physical activity. Exercise-related laryngeal closure is most commonly encountered in athletic individuals and likely affects between 5% and 7% of all young adults and adolescents. The diagnosis of EILO is not always straightforward because features can overlap with exercise-induced asthma/exercise-induced bronchoconstriction. EILO can therefore remain misdiagnosed for years, and most patients receive inappropriate asthma therapy. In contrast with asthma, EILO symptoms are usually most prominent at maximal exercise intensity and resolve quickly on exercise cessation. It is important to recognize that EILO and asthma can coexist in a proportion of athletes. The criterion standard test for diagnosing EILO is continuous laryngoscopy during exercise testing, although eucapnic voluntary hyperpnea testing has also been used. Various surgical or pharmacological interventions can be used to treat EILO, but first-line treatment is breathing technique work. Further research is needed to establish the optimal treatment algorithm, and more work is needed to increase awareness of this important clinical entity.